Tone control wiring?

[Wiker]

Does the order of the tone cap and pot make any difference?
-> cap -> pot -> ground
-> pot -> cap -> ground

Obviously won’t make a difference when the pot is all the way down.
Been reading that the order of components in series doesn’t matter. However, from testing I find that the order of the tone control, 4.7nF inline cap, and volume pot makes a huge difference. So maybe the order of the tone cap and tone pot makes a difference also?
(I’m just not in the mood for much more testing, and thought I’d ask instead. )


I ask because I’m playing with an idea of modifying the tone pot in order to have both the standard 47nF tone cap and a 22nF cap (on the bridge pickup of a bass), but without using a push/pull. To do this I have to change the order of the cap and pot.

[cjj]

No, it won't make any difference, at least as far as those two components are concerned.

I'm not sure I follow what you were doing with the 4.7nF cap configuration, or what you plan to do with the 22nF and no push/pull though. Depending on where you connect things, the order can make a big difference. For instance if you want to connect between the pot & cap to some other circuitry. But in the case shown:

X-> cap -> pot -> ground
X-> pot -> cap -> ground

There will be no difference seen at the beginning node (marked "X")...

[Wiker]

I’m not doing anything with the 4.7nF cap. I was just testing the order of things a while back.
Standard sequence in which the signal meats the different components is:
PU => tone cap+pot > inline cap > volume pot => out
If those three components are ordered differently, it will change things in ways I could not predicted with my limited understand of electronics.

At the moment I’m just looking at the order of the tone cap and tone pot in the standard wiring, and was thinking..
In standard wiring, the full signal meats the tone cap. How much of what comes through the cap goes to ground is regulated by the pot.
If the order is changed, the pot will regulate how much of the original signal meats the cap, and all that comes through the cap goes to ground.
Would that make a difference?

Thing is.. I like the standard 47nF tone cap on the bridge pickup. Rolled down it gives it a nice mellow tone (which I like). However, I also like to use a 22nF cap on the bridge pickup. All the way down a 22nF cleans up the sound without touching much of the punchy midrange from the bridge pickup. At the moment I use push/pull to select 22nF or 47nF, but I got an idea of how to get rid of that push/pull.
Open the pot and cutting the resistive tract close to the upper lug. In effect disconnecting that lug from the track, and making it into a no-load pot. Then the upper lug can be used for a 22nF cap. In practice the tone knob will work as normal with a 47nF cap, almost all the way to the top. At the very top the viper will leave the resistive track, switching out the 47nF cap. The viper then moves to the upper lug, engaging the 22nF cap. If I could also make some kind of detent just before the 22nF is coupled in..

I thought I had to reverse the order of the cap and the pot to do this, but now I see that is of course not necessary.

[cjj]

At the moment I’m just looking at the order of the tone cap and tone pot in the standard wiring, and was thinking..
In standard wiring, the full signal meats the tone cap. How much of what comes through the cap goes to ground is regulated by the pot.
If the order is changed, the pot will regulate how much of the original signal meats the cap, and all that comes through the cap goes to ground.
Would that make a difference?

Ah, I see. Interesting idea with the 22nf and the cut pot track!

As for the order, no it won't make a difference. The way the circuit works is not quite as simple as your description above since, in the AC (alternating current) world, things are always a bit more complicated.

You can think of a cap as being a water tank with an inlet on each end and a diaphragm separating the two ends. Think of the ground as a bucket full of water. If you pump water in one side, it will force water out of the other side too, up to a point. If you just keep the input pressure constant, eventually the flow will stop (this is like DC to a cap, it doesn't pass through after the initial surge).

Now, if you pump water in, then let it out, and repeat, you have the equivalent of AC. Since there going to be water (or current) flowing in and out of both sides (you pump on one, the diaphragm forces water in and out of the other), it won't really matter whether the restriction (resistor or pot) is on the side you are pumping or the side with the bucket. It will slow the flow in either case...

[Wiker]

Ah, I see. Interesting idea with the 22nf and the cut pot track!

The idea is good I think, but unpractical without a mechanism for clicking into a position before engaging the 22nF cap.

[...] it won't really matter whether the restriction (resistor or pot) is on the side you are pumping or the side with the bucket. It will slow the flow in either case...

Great water analogy! Think I understand it a bit better now. Thanks